replace fetch_ready with a "wait needed" input line

2 files changed, 9 insertions, 7 deletions

diff --git a/control_unit.v b/control_unit.v
index 00ebd4f..fa652e0 100644
--- a/control_unit.v
+++ b/control_unit.v
@@ -1,7 +1,7 @@
 module control_unit (
 	input clk,
 	
-	input fetch_ready,
+	input needWait,
 	
 	output fetch_en,
 	output decode_en,
@@ -25,11 +25,13 @@ module control_unit (
 	assign incr_pc = current_state[1];
 	
 	always @(posedge clk) begin
-		case(current_state)
-			10'b1: if(fetch_ready) current_state <= 10'b10;
-			10'b10: current_state <= 10'b100;
-			10'b100: current_state <= 10'b1;
-		endcase
+		if(!needWait) begin
+			case(current_state)
+				10'b1: current_state <= 10'b10;
+				10'b10: current_state <= 10'b100;
+				10'b100: current_state <= 10'b1;
+			endcase
+		end
 	end
 	
 	assign dbg_state = current_state;
diff --git a/nqcpu.v b/nqcpu.v
index a818587..ffb5f31 100644
--- a/nqcpu.v
+++ b/nqcpu.v
@@ -150,7 +150,7 @@ module nqcpu (
 	control_unit control_unit_inst (
 		.clk(clk),
 		
-		.fetch_ready(fetch_ready),
+		.needWait(fetch_en & !fetch_ready),
 		
 		.fetch_en(fetch_en),
 		.decode_en(decode_en),